Logitech Marble Mouse T-BC21 USB Wired Trackball ( TESTED WORKING ) | eBay
Logitech TrackMan Marble FX Trackball
Amazon.com: Logitech Marble Mouse
Amazon.com: Logitech M570 Wireless Trackball Mouse – Ergonomic Design with Sculpted Right-Hand Shape, Compatible with Apple Mac / Microsoft, USB Unifying Receiver, Dark Gray (Discontinued by Manufacturer)